High‐efficiency transmission‐line inverse Class F power amplifiers for 2‐GHz WCDMA systems

In this article, a novel load‐network solution to implement the transmission‐line inverse Class F power amplifiers for base station WCDMA applications is presented. The theoretical analysis is based on an analytical derivation of the optimum load‐network parameters to control the second and third harmonics at the device output, including the device output parasitic shunt capacitance and series inductance. The transmission‐line inverse Class F LDMOSFET and GaN HEMT power amplifiers using NXP BLF6G22LS‐75 and CREE CGH27060F devices, respectively, were designed and measured. The high‐performance results with the drain efficiency of 70.2% and power gain of 18.0 dB for a 60‐W LDMOSFET power amplifier and with the drain efficiency of 82.3% and power gain of 14.3 dB for a 50‐W GaN HEMT power amplifier were achieved at an operating frequency of 2.14 GHz. © 2011 Wiley Periodicals, Inc. Int J RF and Microwave CAE, 2011.